I see a couple of mistakes that I'm going to fix and try to explain why they are mistakes. The first two sentences are fine however.

I'll write the reading of the kanji in parentheses.

「私はカナダいにいます」 → 「私はカナダに住んでいます（すんでいます）」
Your sentence would translate it something to the effect of "I am in Canada" which is a pretty strange way to introduce yourself. 住んでいます means "I am living in" and would fit better in an introduction.

「日本語はわたしに新しいです」 → 「日本語（にほんご）を勉強（べんきょう）していますが、まだ初心者（しょしんしゃ）です」
If I'm guessing correctly the meaning you wanted to convey is "I'm new to Japanese", however it's a literal translation and doesn't make any sense in Japanese, at least it sounds very awkward. So I went for "nihongo wo benkyou shiteimasu ga, mada shoshinsha desu" which roughly translates into "I'm studying Japanese, but I'm still a beginner" thus expressing the same thing that you wanted to get across.

「助ける、お願いします」 → 「間違え（まちがえ）があれば直して（なおして）ください」.
助ける usually isn't used like that, it's more used when you're calling for help or talking about helping someone. "Machigae ga areba naoshite kudasai" basically means "If I there's a mistake, please correct it". 間違え means mistake, あれば is the conditional form(the if-form) of ある and 直してください means "please fix/correct".

Again, welcome to TJP and I hope you enjoy your stay! If you've got anymore questions you're welcome to post them in the appropriate forums